Various project management systems have been suggested. For example, a technology for managing a project on the basis of a human hierarchical structure. Another discloses a technology for managing progress of a project at each milestone. A third discloses a technology for checking progress in real time. A fourth discloses a technology for managing a project by using work breakdown structure (WBS) data. A fifth discloses a technology for integrating a plurality of projects for management. These technologies enable an accurate management of the progress of a project.
When using these technologies, however, progress is sometimes difficult to grasp accurately. For example, a worker inputs an approximate value (%) as progress of a task in some of these conventional technologies. Therefore, the worker's subjectivity lies in the value and it may hinder an objective view on the progress. In some of these conventional technologies, the intervention of the worker's subjectivity is excluded using a checklist, though the checklist is unclear in the relationship between items and tasks and the relationship between lower order tasks and higher order tasks. On the other hand, the checklist generally includes check items that are both relatively important and less important in the project. Therefore, it is still difficult to grasp progress with consideration given to the levels of importance of the check items when using the checklist for project management. Furthermore, although a significant change may occur in the middle of the project, it is difficult to respond to the change in the conventional technologies.